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Water extracts of Ocimum gratissimum, Azadirachta indica, Vernonia amygdalina and Moringa oleifera were evaluated for their effect on pathogenicity of Meloidogyne incognita race 2 and on the growth and yield of cowpea.  Eggs and juveniles of M. incognita were exposed to water extracts from leaves of these indigenous plants for ten days in a completely randomized design with four replicates.  Data on egg hatch inhibition and juvenile mortality were taken daily. Three cowpea cultivars were inoculated with M. incognita and later drenched with the botanical extracts at 10,000 mg/kg and 20,000 mg/kg in pots.  The experiment was laid out in a randomized complete block design with five replications.  Data collected were number of leaves, plant height, grain yield at harvest; nematode population in soil and roots, and the reproductive factor of the nematodes.  Egg hatch inhibition ranged from 40% - 63.7% in the extracts compared to the control with 0%. Juvenile mortality in extracts was from 82% - 93.8% compared to the control with 25%.  Grain yield of plants treated with V. amygdalina at 10,000 mg/kg and 20,000 mg/kg; and 20,000 mg/kg of A. indica, O. gratissimum and M. oleifera were significantly higher than in the untreated plants.  These plants also had nematode reproductive factors comparable to the uninoculated control.  This study therefore shows that low to moderate concentrations of these indigenous botanicals are effective in reducing the pathogenicity of the root-knot nematode and is accompanied by a yield increase in cowpea.